The sterilization of the soil before planting the seeds is a must in order to kill fungi, bacteria and/or soil pests like fungus gnats, which will eventually harm the seeds and later the seedlings. For me, the hot water sterilization works best.
For that purpose, the soil is wrapped in a old cotton kitchen towel and placed in a bowl. Afterwards the bowl is filled with boiling hot water. I leave the soil in it until the water has cooled off so I can press the water out of the soil with my hands.
After cleaning the seedbox throroughly, the sterilizied soil can be placed in the seed box. Before planting the seeds, they must be cleaned thoroughly to remove possible attached organic material. Attached organic material is nourishment for fungi spores and bacteria.
After planting, the seed box has to be covered and closed, to keep the seeds moist and to keep fungi spores and gnats outside. I recommend a 15 Watt heating pad to provide bottom heat for a faster and higher germination rate.
In approximately 10 - 21 days, the first seeds will germinate. The germination may take up to four weeks, until all fertile seeds have germinated.
Healthy seedlings have grown after four weeks
For those, who want to plant occasionly a few seeds and do not want to buy equipment like a heating mat:
